const Koa = require('koa');
const app = new Koa();
const views = require('koa-views');
const cors=require('koa2-cors');
const json = require('koa-json');
const onerror = require('koa-onerror');
const bodyparser = require('koa-bodyparser');
const logger = require('koa-logger');

const index = require('./routes/index');
const users = require('./routes/users');
const login = require('./routes/login');

// error handler
onerror(app);

// middlewares
app.use(bodyparser({
  enableTypes:['json', 'form', 'text']
}))
app.use(json());
app.use(logger());
app.use(require('koa-static')(__dirname + '/public'));

/**
 * 设置允许跨域访问
 */
app.use(cors({
    origin:function(ctx){
      if(ctx.url==="/text"){
        return false;
      }
      return '*';
    },
    exposeHeaders:['WWW-Authenticate','Server-Authorization'],
    maxAge:5,
    credentials:true,
    allowMethods:['GET','POST','DELETE'],
    allowHeaders:['Content-Type','Authorization','Accept', ' X-Requested-With']
}));

app.use(views(__dirname + '/views', {
  extension: 'pug'
}));

// logger
app.use(async (ctx, next) => {
  const start = new Date();
  await next();
  const ms = new Date() - start;
  console.log(`${ctx.method} ${ctx.url} - ${ms}ms`)
});

// routes
app.use(index.routes(), index.allowedMethods());
app.use(users.routes(), users.allowedMethods());
app.use(login.routes(), login.allowedMethods());

// error-handling
app.on('error', (err, ctx) => {
  console.error('server error', err, ctx)
});

module.exports = app;
